One legal scholar calls it "the most important case the Supreme Court will hear this year." That happens to be a gender discrimination case against Wal-Mart, which the Court will hear today. So what exactly makes this case so important?

Dukes v. Wal-Mart is named after Betty Dukes, who along with five other women sued the company for sex discrimination in 2001. In 2004, the Court certified a national class that included not just the women who brought the claim, but all women who had worked at Wal-Mart or Sam's Club since December 1998.

Here's the evidence they brought of widespread discrimination at the stores:

Wal-Mart has (or had) highly subjective promotion and pay raise processes, which aren't posted publicly and don't comply with standard practices in the U.S. workforce, contributing to overall discrimination.

According to the plaintiffs, there is a corporate culture "rife with gender stereotypes, demeaning to female employees: Wal‐Mart executives refer to women employees as 'Janie Qs,' approve holding business meetings at Hooters restaurants, and attribute the absence of women in top positions to men being more aggressive in seeking advancement. For example, women like named Plaintiff Christine Kwapnoski were told men need to be paid more than women because "they have families to support."

All of this has contributed to wage inequality. "Even though its own data shows that its female employees are, on average, better performers and more experienced than their male counterparts, women's pay lags far behind that of male employees in every major job in each of the company's 41 regions." Furthermore, even though "women comprise more than 80 percent of hourly supervisors, they hold only one‐third of store management jobs and their ranks steadily diminish at each successive step in the management hierarchy."

There's also this fun chart comparing Wal-Mart's number of women in management roles to other general-merchandise stores.

In a separate complaint, the plaintiffs pointed out that "female representation among managers at Wal-Mart is at a substantially lower level today than among Wal-Mart's competitors in 1975."

The Court isn't going to hear now about whether the women were indeed discriminated against. Rather, it will decide (by late June 2011) whether these women count as an entire class that can sue en masse. Wal-Mart, obviously reluctant to be sued by every female employee it ever had, counters that because these decisions were made at the store manager level, there is no justification to consider them as part of a monolithic entity.

Writing in Slate, Richard Thompson Ford of Stanford Law School points out that this case is about whether sexism and discrimination constitute a commonality among all women who worked at Wal-Mart. While that may mean that it dilutes the damages paid to the women with the strongest claims, a point raised by judges in earlier stages, it also ensures that there can be systemic social change beyond the claims of individuals. He writes,

Civil rights have always been as much about social justice as individual justice. And social justice requires that employers who discriminate be held accountable so they won't keep discriminating. The deterrent effect of a large class-action lawsuit may be the only thing that will encourage employers to root out discrimination among their managers: Tellingly, Wal-Mart has made an impressive effort to treat women more equitably in the 10 years since the case was filed.

Unfortunately for the plaintiffs and for anyone else interested in advancing social change through class action legislation, Ford writes, the current Supreme Court has preferred to see discrimination as an individual problem rather than a systemic one.